Contact device between a stationary current supply and a movable load



BETWEEN A STATIONARY CURRENT D M 2 m n me ,x/ B 02 N- M 15 0| 2 g I K M N 4 A 1 m A h a CP B nw ES 5 P D 9 T k C m 4 w 1 6 1. W F 2 Dec. 14, 1965 United States Patent Ofilice 3,223,814 Patented Dec. 14, 1965 3,223,814 CONTACT DEVICE BETWEEN A STATIONARY CURRENT SUPPLY AND A MOVABLE LOAD Wolfgang Kalbitz, Erlangen, Germany, assignor to Siemens-Schuclrertwerke Aktiengesellschaft, Berlin, Germany, a corporation of Germany Filed Aug. 26, 1963, Ser. No. 304,354 Claims priority, application Germany, Aug. 29, 1962, S 81,149 11 Claims. (Cl. 200-166) My invention relates to a contact device that electrically connects a stationary current supply and a movable load.

Particularly in the case of contact devices for elements that are insertable in cabinet-like housings with a door contact, as for example those which are used in the treatment of plastic substances at low-pressure gas discharges, contacts are provided at the locations of the inserted elements for connecting the latter, which are made up of the plastic pieces, with a current supply at the supporting portions. It is necessary that the contact device be maintenance-free, simply built and easily interchangeable by hand without any difiiculty, and that contact should be made in such a way that there will be protection against spray discharge at low-pressure gas discharges.

It is an object of my invention to provide a contact device for electrically connecting a stationary current supply with a movable load that will have the foregoing advantageous features.

It is another object of my invention to provide such a contact device that will readily cut off any spray discharges that may tend to occur.

It is a further object of my invention to provide such a contact device that will be self cleansing.

To this end and in accordance with one aspect of my invention, I provide a dumbbell-shaped contact member having a first predominantly spherically-shaped end and a second outer hemispherically shaped end. The contact member extends into a bore operatively disposed in an essentially horizontal position in an insulating support body on the side of the load or current consuming device, the bore having a size corresponding to the diameter of the sphere at the aforementioned first end of the contact member. The hemispherically-shaped portion extends into a larger bore in the support body and locks therein in such a way that the resiliently formed current supply lead near the load, which lies up against the contact piece, presses the contact piece which is operatively inclined to the axis of the bore, against the load.

According to another aspect of my invention and due to the particular configuration of the contact member, i.e. the spherical shape, the field intensity at the upper surface is so reduced that spray discharges are able to be cut off easily. Due to the rotational symmetrical form of the contact body relative to the connecting piece between the two end portions, the contact piece is able to turn so as to automatically wipe the contact surfaces when the load is placed in position and the resilient current supply means applies counterpressure thereto.

Other features which are considered as characteristic of the invention are set forth in the appended claims. The invention, however, both as to its construction and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of a specific embodiment thereof when read in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of the contact device embodying my invention in which the device is shown in a position in which it is not electrically conducting;

FIG. 2 is the same view as in FIG. 1 with the contact device in electrically conducting position; and

FIG. 3 is a fragmentary view, partly broken away, showing a modification of the contact device of FIGS. 1 and 2.

Referring to the drawings and first to FIGS. 1 and 2, the contact device embodying my invention is shown respectively in the inoperative and operative position thereof. A dumbell-shaped contact element 1, having a spherically shaped end 2 on the load side thereof and an essentially hemispherically formed end 3 on the current supply side thereof, is inserted from the load side through a bore 6 of substantially the same diameter as both ends 2, 3 into the insulating support body 8. The contact element 1 extends into the bore 6 of the body 8 such a distance that the hemisphericallyshaped end 3 comes into engagement with a current supply lead or conductor 11 which is provided on the opposite side of the support body 8, while the spherically-shaped end 2 remains partly projecting out of the bore 6. In order to prevent the inserted contact element 1 from falling out, the bore 6 is provided with an enlarged portion 7 which forms an internal shoulder having a rear face for the bore 6. The flat face 5 of the hemispherically formed end 3 abuts against the face 9 of the shoulder under the biasing influence of the resilient force supplied by the current supply conductor 11 which is partly divided at 12 opposite the return lead 13 to form a flap-like leaf spring which provides the biasing action. The connecting element 4 of the contact device thus lies in a position in which it is inclined to the axis of the bore.

In the inoperative position of the contact element as shown in FIG. 1 there is a small clearance between the springy current supply conductor 11 and the hemispherically shaped end 3 of the contact member. This clearance is necessary so that the end 3 can drop freely downwardly in every case by force of gravity so as to come to rest in the large bore 7. As soon as a connector 10 of a load, which is not shown in the drawings, for example as insert box, is directed into engagement with the spherically-shaped end 2, the contact element 1 is then displaced toward the right, as shown in FIG. 2, into the operative position of the contact element in which the load is electrically connected and completely advanced.

It is seen in FIG. 2 that the current supply lead 11 is bent outwardly by the hemispherically-shaped end 3 of the contact member. In the embodiment illustrated, the rear side of the support body 8 which is shown as being formed of ceramic insulating material, is protected against external contact at least at the location of the current supply lead 11 by a cover 14. There is provided at least in the vicinity of the springy portion of the current supply lead 11, a recess 15 in the cover 14 which permits the current supply lead 11 to be displaced by the contact element when it is shifted toward the right.

FIG. 2 shows how the springy portion 11 of the current supply conductor projects into the recess 15. To ensure the desired operation of the contact device, it is necessary that the length of the contact element 1 be greater than the thickness of the insulating support body 8. In order to make possible the easy interchangeability of the contact elements, means for manipulating the contact element is provided on the outwardly extending surface of the spherically-shaped end 2, as shown in FIG. 3. The spherically-shaped end 2 is formed with a central bore 16 extending partially therein in which a handle or gripping means 17 is friction-fitted or threaded so that the contact element 1 can be readily inserted and removed from the bore 6. Under certain circumstances it is also desirable that the contact surfaces of the sphericallyshaped portion 2 which are engaged by the connection 10 be provided with special contact bodies which either surround the central bore 16 or are easily and interchangeably inserted therein.

While my invention has been illustrated and described as embodied in a particular contact device, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing from the spirit of the present invention and within the scope and range of equivalents of the following claims.

I claim:

1. In a contact device between a stationary current supply and a movable load, an insulating support having a pair of opposing sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; and a dumbbell shaped contact element received in said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore.

2. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore; and a springy conductor connected to the current supply, said springy conductor resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

3. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposing sides and formed with an elongated bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore, said contact element being longer than the combined lengths of said bore portions and being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore; and a springy conductor connected to the current supply, said conductor resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

4. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partially disposed in said bore portion of reduced diameter and being provided with contact means f or engaging the load and said hemispherical end being at least partially disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore; and a springy conductor connected to the current supply, said conductor resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load. 7

5. In a contact device between a stationary current supply and a movable load, an insulating support having a pair of opposing sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partially disposed in said bore portion of reduced diameter and said hemispherical end being at least partially disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore; and gripping means secured to said spherical end and extending out of said bore for inserting and removing said contact element from said bore.

6. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being formed with a radial bore and being at least partly disposed in said bore portion of reduced diameter, said hemispherical end being at least partly disposed in said bore portion of larger diameter, and the axis of said element being inclined to the axis of said bore; gripping means for inserting and removing said contact element from the bore extending through said insulating support, said gripping means being inserted in said radial bore formed in said spherical end; and a springy conductor connected to the current supply resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

'7. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides, a dumbbell-shaped contact element received in said bore and having an axis inclined to the axis of said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter, said predominantly spherical end being formed with a threaded radial bore; gripping means for inserting and removing said contact element from the bore extending through said insulating support, said gripping means having an externally threaded portion threadedly secured in said radial bore of said predominantly spherical end; and a springy conductor connected to the current supply resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

8. A contact device between stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore and having an axis inclined to the axis of said bore, said contact'element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter, said predominantly spherical end being formed with a radial bore and being provided with contact means for engaging the load, said contact means surrounding said radial bore; and a springy conductor connected to the current supply resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

9. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore and having an axis inclined to the axis of said bore, said contact element being provided with a substantially hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said substantially hemispherical end being at least partly disposed in said bore portion of larger diameter, said predominantly spherical end being formed with a radial bore and being provided with contact means for engaging the load, said contact means being replaceably inserted in said radial bore; and a springy conductor con nected to the current supply, said conductor resiliently engaging said contact element and pressing the same against the load for electrically connecting the current supply and the load.

10. A contact device between a stationary current supply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore and having an axis inclined to the axis of said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter; and a springy cond uctor connected to said current supply, said springy conductor resiliently engaging the hemispherical end of said contact element on the other side of said insulating support and pressing the same against the load for electrically connecting the current supply and the load.

11. A contact device between a stationary current sup ply and a movable load comprising an insulating support having a pair of opposed sides and formed with a bore extending between said sides, said bore having a portion of reduced diameter adjacent one of said sides and a portion of larger diameter adjacent the other of said sides; a dumbbell-shaped contact element received in said bore and having an axis inclined to the axis of said bore, said contact element being provided with a hemispherical end and a predominantly spherical end having a diameter corresponding to that of the reduced diameter bore portion, said predominantly spherical end being at least partly disposed in said bore portion of reduced diameter and said hemispherical end being at least partly disposed in said bore portion of larger diameter; a springy conductor connected to said current supply, said conductor resiliently engaging the hemispherical end of said contact element on the other side of said insulating support and pressing the same against the load for electrically connecting the current supply and the load; and cover means secured to the other side of said insulating support, at least in the vicinity of said current supply conductor, said cover means being formed with an inner recess into which said current supply conductor and the hemispherical end of said contact element project when the load is connected to the current supply.

No references cited.

KATHLEEN H. CLAFFY, Primary Examiner. 

1. IN A CONTACT DEVICE BETWEEN A STATIONARY CURRENT SUPPLY AND A MOVABLE LOAD, AN INSULATING SUPPORT HAVING A PAIR OF OPPOSING SIDES AND FORMED WITH A BORE EXTENDING BETWEEN SAID SIDES, SAID BORE HAVING A PORTION OF REDUCED DIAMETER ADJACENT ONE OF SAID SIDES AND A PORTION OF LARGER DIAMETER ADJACENT THE OTHER OF SAID SIDES; AND A DUMBBELL SHAPED CONTACT ELEMENT RECEIVED IN SAID BORE, SAID CONTACT ELEMENT BEING PROVIDED WITH A HEMISPHERICAL END AND A PREDOMINANTLY SPHERICAL END HAVING A DIAMETER CORRESPONDING TO THAT OF THE REDUCED DIAMETER BORE PORTION, SAID PREDOMINANTLY SPHERICAL END BEING AT LEAST PARTLY DISPOSED IN SAID BORE PORTION OF REDUCED DIAMETER AND SAID HEMISPHERICAL END BEING AT LEAST PARTLY DISPOSED IN SAID BORE PORTION OF LARGER DIAMETER, AND THE AXIS OF SAID ELEMENT BEING INCLINED TO THE AXIS OF SAID BORE. 